Fujii H, Shinya E, Shimada T
Clinical Hematology Branch, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD 20892.
FEBS Lett. 1992 Dec 7;314(1):33-6. doi: 10.1016/0014-5793(92)81455-u.
The human dihydrofolate reductase and mismatch repair protein 1 genes are organized in a head-to-head configuration separated by an 88 base-pair segment and directed by a bidirectional promoter. In vivo transient assays of the site directed mutant promoters using firefly luciferase as a reporter showed that an AT-rich sequence, ACAAATA, in the GC-rich promoter sequence is not required for transcription. However, two out of four GC boxes were shown to function as bidirectional positive regulatory elements. Among them, a GC box at the midpoint of the region between the two initiation sites is essential for supporting minimal bidirectional activity.
